Method of treating carbonaceous material in an electric furnace or the like



Oct. 15, 1929. J. J.. NAUGLE 1,731,473

METHOD OF TREATING CARBONACEOUS MATERIAL IN AN ELECTRIC FURNACE OR THELIKE Filed April 21, 1923 2 Sheets-Sheet 2 lNl/EIVTUR JOHN J .NAUGLE ATTORNEY Patented 0a. 15, 1929 UNITED STATES PATENT, OFFICE dorm NAUGLE,or BROOKLYN, new Yoax IIETHOD 0F TREATINQ CARBONACEOUS MATERIAL IN ANELECTRIC FURNACE OR THE LIKE Application filed Apri121,

My present invention relates to methods of treating carbonaceousmaterial, particularly comminuted carbonaceous material, such ascomminuted carbonized lignin residues obtained by carbonizingthe wasteliquors derived from the treatment of Wood by the alkali (soda) processin the production of wood pulp, for the production from the materialsdesignated of a very pure grade of carbon characterized by a very lowash or mineral content, high conductivity, and a remarkably high degreeof activation corresponding to a high degree of decolorizing power. Itis an object of the present invention to devise methods of the characterspecified above which shall be exceedingly simple in operation,requiring comparatively simple apparatus and a minimum of time, laborand material for this purpose; which shall produce the desired productin the desired condition of high purity, high conductivity and a highdegree of activation and decolorizing power; and which shall renderpossible a very high yield of the desired product in proportion to theraw material used and the amount of power consumed.

In the accompanying specification I shall describe an illustrativeembodiment of the method of the present invention. In the accompanyingspecification I shall also describe, and in the annexed drawing show,one form of apparatus in which the method of the present invention maybe conveniently practiced. It is, however, to be clearly understood thatmy invention is not limited to the specific embodiment of the processdescribed herein, nor to the use of the particular form of apparatusshown and described herein, said apparatus forming the subject matter ofa separate application for Letters Patent filed by me of even dateherewith.

Inorder that my invention may be more clearly understood,'reference maybe made to a co-pending application of mine, filed of even dateherewith, .Serial No. 633,643 and entitled Process for the treatment ofcom minu'ted carbonaceous materials and the like,

in an electric furnace and the like.

In practicing the aforesaid illustrative embodiment of the method of thepresent in- 1923. Serial No. 633,640.'

vention, I take first any suitable raw material, preferably acarbonaceous material in comminuted or finely divided form. Whilevarious types of comminuted carbonaceous material may be treated withsuccess in accordance with the principles of the present invention,either in the production of a highly activated carbon from the rawmaterial, or 111 the revivification of spent decolorizing carbon, Ishall describe the present invention as applied more particularly to thepreparation of a highly activated-carbon from carbonized lignin residuesin comminuted form, such residues being obtained by carbonizing thecooking liquors derived from the treatment of wood by the alkali processin the production of wood pulp.

Taking, for example, the raw material specified above, which comprisescomminuted carbonized lignin residues, such material may have an averageanalysis as follows:

Analysis of ooomm'nuted carbonized Zz'gm'n residues Carbon fi Ash 10Analysis ofiash. Silicious matter 0.13 Silica I. 0.75 Ferric oxide 0.34Alumina 0.47 Lime, CaO 0.23 Magnesia, MgO 0.11 Chlorine as chlorides0.47 Sulphuric anhydride 2.65

Carbon dioxide 1.00

Alkalics (by diff.) 3.85

This material contains certain volatile mat- I fied above so as to expelthe volatile substances and to fuse the mineral substances,characterized by a higl. resistivity, for the subseqiient removal ofsuch fused mineral substances. This 1 preferably do by passing anelectric current of regulated densit through the mass of the rawmaterial untll 5 the mineral substances present therein have been fused.The degree of current employed should be such as to cause the mineralsubstances to aggregate or sinter together in the formation of clinkers.

The fused mineral substance is now removed in any suitable manner so asto yield a product which is characterized, by a very high conductivity,an'iounting often to as much as five times the conductivity of the rawmaterial treated, and characterized, further, by a very substantialreduction in the mineral content of the final substance, which mineralcontent is often reduced to as little as one-fourth or less of themineral content of the original raw material treated.

- l find that the conductivity of theiinal prodnet is a function of thedegreeof activation or decolorizing power of such material, or viceversa, increased conductivity indicating increased activation anddecolorizing power, and vice versa. Accordingly, by the removal of thefusible mineral substances, which are of comparatively high resistivityand which, therefore, reduce the conductivity of the final product, 1 amenabled to effect a very remarkable increase in the degree of activationand decolorizing power of the material treated in accordance With theprinciples of the method of the present invention.

The present method may be combined with considerable success with themeans and method described and claimed in my copending application,filed May 22, 19:22, Serial No. 562,828, and entitled Prefiltering meansand method, especially so far as the preliminary treatment of the rawmaterials is con cerned, particularly to effect by'decantation from awatery suspension of such material a partial preliminary separation bygravity of the portions of the material richer in car bon from theportions of the material poorer in carbon and containing an excess ofheavy mineral substances. 1 may also use the feature of effecting apurification of the final product by forced filtration, under pressure,through a layer of the final product, of an aqueous acidified fluid andof wash waters. 1 may also add to the charge of material being treatedin accordance with the principles of the methodof the present invention,certain reagents, such as sodium fluoride, which. will have the propertyof eliminating one or more of the mineral substances present in thecharge, particularly silica, in the form of volatile by-products, suchas silicon fluoride.

The resulting product possesses many advantages for the intendedpurpose, since it can be very cheaply made in accordance with the methodof the present invention, and possesses the desired quality of highconductivity, corresponding to a remarkably high degree of activationand decolorizing power.

An average analysis of such material is as This product is alsocharacterized by a very high degree of purity, corresponding to a highconductivity and a high degree of activation and decolorizing power. Thecondutivity of the final product is often increased as much as fivetimes that of the raw material treated, and its mineral content is oftenreduced to as low as one-fourth or less that of the raw material treatedin accordance With the method of the present inven-- tion. The methoditself is exceedingly simple to practlce, requiring comparatively simpleapparatus and a minimum of time, labor. power and material for thispurpose. The

methodis also admirably calculated to produce the desired end product inthe desired condition of purity, high conductivity, and high activationand decolorizing power. The method is also very economical in View ofthe very high yield which may be obtainedby its practice as comparedwith the methods liitherto employed for revivifying spent decolorizmgcarbon or for producing highly activated carbons for decolorizingpurposes.

Referringto the drawing wherein T have illustrated one form of apparatusin which the method outlined above may be conveniently practiced:

Fig. 1 is a view in longitudinal section,

partly broken away, and partly in elevation,

showing the furnace comprising the aforesaid form of apparatus;

Fig. 2 is a cross-sectional View of the same taken along line 2-2 ofFig. 1 of the draws;

Fig. 3 is a cross-sectional view of the same taken along line 33 of Fig.1 of the drawmg;

Fig. 1 is a view similar to Fig. 3 taken along line 1-4 of Fig. 1 of thedrawing; and

Fig. 5 is an enlarged detail longitudinal sectional View at the outletend of the machine.

Referring to the aforesaid form of ap herein, I provide means vingbearing sleeves'15-and 16 for paratus in which the aforesaidillustrative embodiment of the method ofthe present invention may beconveniently practiced, the furnace comprising such apparatusincludessubstantially cy-' d bars 20, which members are the casing 10,preferably lindrical form, having the inlet tube 11 an the outlet tube12, sa d-tubes being likewise of substantially cylindrical form andcom-- material and the proper distributionjof current through the massbeing treated.

The electrodes 20 tudinally' arranged knobs or studs, prefer ablylocated on both sides of each of the memsulating material or are pro soas to avoid connection wit the electrodes,

are in the form of lon i;

prefe'rablyof inrly insulated,

rising bearings for the casing 10. The cas-' and also to avoidshort-circuiting the furnace .mg and'the tubes 11 and 12 are supportedthrough the metallic portions of the casing by apluralityof'standards13-and 14, provldand other parts of the machine. While iva-v the tubularbearings 11 and 12.

In the form illustrated by way of example referably continuous, of thetion, which is t e parts carried by and with- -casing 10 and in thesame.

' suitable means such as the annular toothed from of the material andthe proper some or all of the members gear 17 carried by and surroundingthe casi mg 10, and adapted to cooperate with a spur ear or pinion18carried by a shaft 19"driven roin any suitable source of deemednecessary ing of the gears 17 and 18, the casing 10 and its associatedparts may rate 'of speed.

' Within the casing 10 are a plurality of stirring and mixing also assupports for the electrodes, said members being generally indicated byreference character 20. Each of the members 20 is preferably replaceableor readily-removable the casing 10, as by having each such member passthrough an opening or orifice 21 in the wall of the casing 10. By meansof suitable bolts 22, passing through flanges 23 forming apart of thebase24= of each member 20., each member 20 may be readily installed andasreadil'y removed for cleamng, repair or replacement, as desired.

, In order to bring about an effective mixing distribution of I preferto. provide 20 with a hollowedout surface for the'reception andsubsequent discharge of a portion of the material in the furnace. Forthis purpose, that face of each current through same,

' or some of the members 20 which, during the rotation of the casing 10,first comes into contact with the material M in the furnace, is dishedout or made slightly concave, as indicated at 25.-' 4 It 'will be notedthat each set of members 20 is disposed in spaced relation along thecircumferential periphery of the inner face 10 of the casing 10. It willalso be noted that themembers 20 of each such set are substan tiallyradially disposed. I have found, by

eriment, that this' disposition of the same is of considerableimportance for the proper treatment of the material within.

' tion to the process already described will be the furnace, by insuringproper mixing of the for effecting a rota- Forthis purpose, Iprovide-any.

power not here to be shown. By the meshbe rotated at any desired 4 ringsmembers, which mayserve 'bular outlet ends of the casinglO,respectively, and suitably insulated ture of the same.

from the metallic struc- At 32 and 33 I have indicated the leads orwires for supplying current to the conductor rings 30 and 31,respectively. I prefer that the electrodes20', of. whichseveralperlpheral sets or rows, here shown as lifn peripheral rows eachincluding ei ht peripherally disposed electrodes, may ployed-,'shall beso connected to the conductor and 31, and the leads 32 and 33 supplyingcurrent thereto, that "successive elec trodes in each peripheral setwill be oppositely charged and that successive electrodes in.

eem-DO' each longitudinalset will be likewise oppositely char d findthat'this arrangement of electr es is highly desirablein that itassists' in effecting the proper distribution of current through thechargeof materialwithin the 79 furnace. r

In order to continuously feed material into ,the furnace for treatmentand out of the fur* nace after the same has been subjected to thedesired treatment for the desired time, I

provide any suitable means, but preferably an inlethopper 40 for feedingun-- treated material into the machine through the V tubular bearing 11.The tubular bearing 11 length of.

communicates with the central chamber 411 of a spiral feeding device,generally indicated by reference character 42. The spiral feeding device42. is located at the inlet end of the machine, and is provided with thedischarge openings 43 leading into the heating chamber 10" within thecasing 1'0. Similarly, the discharge outlet is in the form of a conduitH communicating at its upper end with the tubearing 12 which leadsintothe central opening 15 of a spiral outlet feeding device',

generally designated by referencecharacter 46, and similar in-mostrespects to the spiralinlet feeding device 42. The feeding device 46 hasthe inlet openings 4 communicating with the spiral passage in thefeeding device 46 for the admission of treated material for itssubsequent discharge from the ma-- chine. J

The operation of the machine and its relascription and may be briefiy'summarized as follows: Comminuted carbonaceous material, particularlycomminuted carbonized lignin residues, generally indicated by referencecharacter M, is continuously fed into the 1 machine through the hopper40 and the feeding means/12, and thus enters the heating chamber whereit is brought into oper- 1O ative contact with the electrodes Theelectrodes -20','.by'the continuous rotation of the casing 10 carryingthe same, are brought into intermittent contact with the material M andserve to intermittently and continuousxm ly stir and mix the same. Thisdesired action is facilitated by the particular form which the members20 possess. This form, resulting from the dished-out surfaces with whichthese members are provided, serves to cause the members20 intermittentlyto receive and subsequently to discharge a portion of the material Mbeing treated Within the furnace.

The course of such material is diagrammatically illustrated in Fig. 2 ofthe drawing,

-25 which approximates the position of the mass of material M within thecasing for a particular speed of operation 'of the machine.

What I claim as m invention is:

1. The method of treating carbonaceous material to obtain a highlyactivated, decol-- orizing carbon therefrom, which" comprises heating amass of such material to fuse a art at least of the mineral contentthereof w ile passing collecting m'embers through tliecmass to removethe fused material from the same.

2. The method of treating carbonized lignin residues to obtain a highlyactivated, decolorizing carbon therefrom, which 'comprises heatinga massof such material by pass ng an e fuse a part at least of the mineralcontent thereof While passing collecting members through the mass toremove the fused material from the same.

3. The, method of treating carbonaceous materialto obtain a h orizingcarbon therefrom, which comprises pa'ssing a plurality of electrodesthrough a mass of such material to heat the same sufficiently to fuse apart at least of the mineral content of the mass while stirring thesame.

4. The method of treating carbonaceous ectric current therethrough toighly activated, decol material to obtain a highlyactivated,.decolorizing carbon therefrom, which comprises The electrodes20 srve, by reason of their passing a plurality of electrodes througgmaconnection with the conductor rings and 30 31; and the lead wires 32 and33 supplying current thereto, to discharge a current of regulated andcontrolled density through the mass M of material being treated in thefurnace. The current should be such as to read 35 ily volatilizevolatile matter contained in the minutes. The resulting product, inaddition to the desirable properties already specified, possesses a highdegree of neutrality, which is very desirable, and possesses also adecolorv izing power substantially, and often as'much as ten per cent,greater than the best activated carbons hitherto produced. The resultingproduct is described and claimed in a copending application filed by meof even date herewith.

It may here be stated that the carbonized lignin residues referred toherein are the res1- dues remaining after leaching the residues obtainedby carbonizing the spent pr used cooking liquors obtained in thetreatment ofwood by the alkali (soda) process in the treatment of woodpulp; and that the terms activation and decolorizing, or theirequivalents, as used in'the specification and'claims, include alsodeodorization, purification and filtration.

mass of such material to heat the same s ciently to fuse a part at leastof the mineral content of the mass while stirring the-same to collectandremove therefrom the fused macolorizing carbon therefrom, whichcomprises continuously passing an electric current of regulated densitythrough the mass,

from electrodes extending into the same, to

fuse'a part at least of the mineral content of the mass, andcontinuously removing the Y fused material therefrom.

7. The method of treating 1 carbonaceous material to obtain a highlyactivated, decolorizing carbon therefrom, passing an electric curren ofregulated density through the mass, from electrodes passinginto andthrough the same, to fuse a part at least of the mineral content of themass and removing the fused material therefrom by adhesion of said fusedmaterial to said electrodes.

8. The method of treating carbonized lignin residues to obtain a highlyactivated, decolorizing carbon therefrom, which comprises continuouslypassing an electric current of regulated density through the mass, fromwhich comprises electrodes passing through the same, to fuse a part atleast of the mineral content of the mass, and continuously removing thefused material therefrom by adhesion of said fused material to saidelectrodes.

9. The method of treating carbonaceous material to obtain a highlyactivated, decolorizing carbon therefrom, which comprises passing anelectric currentof regulated density through the mass, from electrodesextending into the same and in the presence of foreign electricallyconductive bodies, to fuse a part at least of the mineral content of themass, and removing the fused material therefrom.

10. The method of treating carbonized lignin residues to obtain a highlyactivated, decolorizing carbon therefrom, which comprises continuouslypassing an electric current of regulated density through the mass, fromelectrodes extending into the same and in the presence of foreigncarbonaceous bodies of comparatively great conductivity, to fuse a partat least of the mineral content of the mass, and continuously removingthe fused material therefrom.

11. The method of treating carbonaceous material to obtain a highlyactivated, decolorizing carbon therefrom, which comprises passing anelectric current of regulated density through the mass, from electrodespassing into and through the same and in the presence of foreign bodiesof comparatively great conductivity, to fuse a part at least of themineral content of the mass, and removing the fused material therefromby adhesion of said fused material to said electrodes.

12. The method of treating carbonized lignin residues to obtain a highlyactivated, decolorizing carbon therefrom, which comprises continuouslypassing an electric cur: rent of regulated density through the mass,

from electrodes passing through the same, and m the presence of addedcarbonaceous bodies of comparatively great cont'luctivity, to fuse apart at least of the mineral content of the mass, and continuouslyremoving the fused material therefrom by adhesion of said fuz-"edmaterial to said electrodes.

13. The process of continuously treating carbonaceous material, such ascarbonized lignin residues, which comprises heating a mass of suchmaterial suflicient-ly to fuse a part at'leastof the mineral contentthereof, continuously removing said fusible material, continuouslyadding untreated portions of material to the mass of material beingtreated, and continuously removing portions of treated material from theheating zone.

14. The process of continuously treating carbonaceous material, such ascarbonized lignin residues, which comprises heating a mass of suchmaterial, by passing an electric current of regulated densitytherethrough,

sufficiently to fuse apart at 1 ast of ic mineral content thereof,continuously rel roving said fusible material, continuously addinguntreated portions of material to the mass of material being treated,and continuously removing portions of treated material from the heatingzone.

1t". The process of continuously treating carbonaceous material, such ascarbonized lignin residues, which comprises heating a mass of suchmaterial, by passing an electric current of regulated densitytherethrough from electrodes rotating through the mass of material beingheated. sufliciently to fuse a part at least of the mineral contentthereof, continuously removing said fusible material, continuouslyadding untreated portions of material to the mass of material bengtreated, and continuously removing portions of treated material from theheating zone.

16. The process of continuously treating carbonaceous material, such ascarbonized lignin residues. which comprises heating a mass of suchmaterial, by passing an electric current of regulated densitytherethrough from electrodes rotating through the mass of material beingheated, suflicient- 1y to fuse a part at least of the mineral contentthereof, continuously removing said fusible material, continuouslyadding untreated portions of material to the mass of material beingtreated, and, continuously removing portions of treated material fromthe heating zone by adhesion of said fused material to said electrodes.

17. The method of treating carbon lignin residues containing mineralimpurities to obtain a highly activated carbon therefrom, whichcomprises heating a mass of such material in an electric furnace in thepresence of an addition agent to thereby volatilizea part, at least, ofthe mineral impurities present in such material.

18. The method of treating carbon lignin residues containing siliciousmineral impurities to obtain a highly activated carbon therefrom, whichcomprises heating a-mass of such material in the presence of a fluorideto thereby volatilize a part, at least, of the silicious mineralimpurities present in such material.

19. The method of treating carbonized lignin residues containing mineralimpurities to obtain a highly activated decolorizing carbon therefrom,which comprises passing a heating electric current of regulated densitythrough a mass of such material in the presence of an addition agent tothereby volatilize a part, at least, of the mineral impurities presentin such material.

20. The method of treating carbonaceous material to obtain a highlyactivated carbon therefrom which comprises heating a mass of suchmaterial in an electric furnace to fuse a part at least of the mineralcontent thereof, in

the presence of an addition agent to thereby volatilize a part at leastof the mineral content of the mass.

21. The method of treating carbonaceous material to obtain a highlyactivated carbon therefrom which comprises heating a mass of suchmaterial in an electric furnace to fuse a part at least of the mineralcontent thereof, in the presence of an addition agent to therebyvvolatilize a part at least of the mineral content of the mass whileagitating said mass.

22. The method of treating carbonaceous material to obtain a highlyactivated carbon therefrom which comprises heating a mass of suchmaterial to fuse a part at least of the mineral content thereof, saidheating being in the presence of a fluoride to thereby volatilize a partat least of the mineral content of the mass.

I 23.- The method of treating carbonaceous material to obtain a highlyactivated'carbon therefrom which comprises heating a mass of suchmaterial to fuse a part at least of the mineral content thereof, saidheating being in the presence of a fluoride to thereby volatilize a partat least of the mineral content of the mass while agitating said mass.

24. The method of obtaining a highly activated carbon which comprisesheating carbonaceous material in an electric furnace to fuse a part atleast of the mineral content of the carbonaceous material while passingcollecting members through the material to remove the fused materialfrom. the carbonaceous material.

In testimony whereof, I have signed my name to this specification this30th day of March, 1923.

JOHN J NAUGLE.

